The focus of the project is a 45-year prospective study of aging in healthy male adolescents. The study includes two cohorts: (A) the COLLEGE SAMPLE -- 204 college sophomores selected in 1940-42 for mental and physical health and high achievement; (B) CORE CITY SAMPLE -- 460 11-15 year old boys selected by the Gluecks as non-delinquent controls in 1940-44 from high crime neighborhoods and inner city schools. Both samples have been followed until 1977. Except for death, attrition has been only 5%. Many independent ratings of mental health of each subject in childhood, in young adulthood, and in middle life exist. Until 1984, the present study will prospectively follow the significant deterioration of physical health in these 664 men. Repeat physical examinations will be obtained on the COLLEGE SAMPLE at ages 58 and 63, and on the CORE CITY SAMPLE at age 53. Records of hospitalization and illness patterns will be obtained on all men. An internist, blind to earlier mental health, will evaluate the physical deterioration in each subject (i.e., onset of chronic illness, permanent disability and death). Major questions asked will be: (1) How does pre-existing mental health affect deterioration of physical health? (2) What familial, childhood and premorbid psychological variables are associated with early aging and/or superior health? (3) What are the lessons of the study for preventive health maintenance?